Dehydrator



NOV. 5, 1946. p MCHOLS, JR 2,41Q675 DEHYDRATOR Filed Feb. 22, 1945 3 Sheets-Sheet l BY Q way/7 PMMo/gdn I A. P. NICHOLS, JR 2,410,675

' DEHYDRATOR Filed Fe b. 22, 1945 3 Sheets-Sheet 2 IN V EN TOR.

I 4 TTOIF/VE-K Nov.5, 1946. A. P. NICHOLS, JR

DEHYDRATOR Filed Feb. 22, 1945 3 Sheets-Sheet 3 Arm/Wm Patented Nov. 5, 1946 UNITED STATE Claims.

This invention relates to dehydrators and particularly mechanical structure for removing the moisture from materials such as plants in the nature of grasses, alfalfa, and other crops.

The primary aim of this invention is to provide a dehydrator of a portable character, having as a part of its assembly, means for motivating a housing or jacket within which is provided a dehydrating chamber; means for supplying fuel to the burners of the dehydrator; means for directing air under pressure into an inner drum forming a part of the structure; and apparatus for motivating the material being treated, longitudinally of the dehydrating chamber and for urging the material upwardly toward specially disposed openings where the products of combustion and hot air from the heating chamber of the dehydrator are directed in counterflow against the said material.

A further aim of this invention is the provision of a dehydrator having the general characteristics as above set forth, but having therein unique and novel means for handling the material being treated, to the end that it will not become burned, subjected to temperatures of objectionable intensity, and will pass through the dehydrator with exceptional speed'whereby production at relatively low cost is permitted.

More specifically, the instant invention has for other aims the provision of a dehydrator having an internal drum forming a fire box and a circumscribing jacket between which and the said drum, a dehydrating chamber is formed. The chamber has therein a number of units or an element for motivating the material being treated, longitudinally through the dehydrating chamber and for urging the material upwardly along the sides of the dehydrating chamber toward a number of specially arranged and positioned openings formed through the inner drum and angled to direct jets of air and products of combustion into the dehydrating chamber in a direction counter to that through which the material is upwardly urged,

* Other objects and aims of the instant invention are to provide a dehydrator with openings of the aforementioned type that are spaced apart distances which progressively increase as the outlet port of the dehydrating chamber is approached, and which are progressively greater distances above the bottom of the dehydrating chamber as said outlet port is approached-all to the end that the material is treated with fewer jetsof hot air as the moisture content thereof diminishes.

Still further objects will appear during the course of the following specification, referring to the accompanying drawings, wherein:

l. is a side elevational View of a dehydrator made in accordance with the present invention.

Fig. 2 is a vertical sectional II-II of Fig. 1.

Fig. 3 is an elevational view dehydrator.

4 is a fragmentary longitudinal central sectional view through the upper portion of the dehydrator, illustrating the relation between the inner drum and outer jacket, which form the dehydrating chamber.

Fig. 5 is a vertical cross sectional View through the dehydrator assembly, taken on line V-V of Fig. 1 and looking in the direction of the arrows,

Fig. 6 is a fragmentary sectional view through a length of the jacket of a dehydrator made in accordance With a modified form of the invention; and

Fig. 7 is a vertical sectional view taken on line VII-VII of Fig. 6.

The form of dehydrator selected for illustration and shown in Figs. 1 to 5 inclusive, comprises a stationary drum l0 having an annular wall and end walls formed or lined with refractory materials and mounted upon suitable frame-work I2.

Drum iii has a pair of burners id operably joined to a source of fuel through the medium of a pipe it. In the instance illustrated, pipe It extends to a drum l3 wherein is stored such fuel as is now well-known in the trade. A valve 2% both manually and automatically operable, controls the flow of fuel through pipe it to burners i t and these burners are supplied with electrodes 2?. joined to a source of electrical energy, not here shown, through conductors 24. These electrodes 22 are mounted directly in front of each of the two burners it, as illustrated in Fig. 5, and a. spark gap is thereby presented to insure that the combustible mixture passing through burners it will not accidentally fill drum ill and cause damage due to explosion. A constant arc is maintained across the gaps between electrodes 2. 2, as a precautionary measure,

It is necessary to maintain a pressure within drum I0 and to that end, a blower or fan til is mounted upon frame l2 and connected to drum It by at least two pipes 32 that extend substantially the full length of drum iii. These pipes have apertures 36 therein and as blower 3:0 is operated by engine 33, air under pressure will be introduced into drum it).

A baille plate ill is mounted below pipes to view taken on line of one end of the 3 protect the same against destructive action of the flame or fire which is created in drum If) by burners Hi.

Connection to blower ill! from engine 38 may be through any suitable medium and it will be understood that power from engine 38 is readily transmitted to blOWer so by way of shaft 42, sprocket 44, chain 46 and sprocket 58 mounted directly upon shaft 56 forming a part of the conventional blower 30. Shaft 42 is connected to engine through the medium of conventional V-belt and sheave wheel assemblies, broadly designated by the numeral 52. A speed reducer 55 is also driven by engine 38 and the \"-belt and pulley wheel train 56 and 58, has a clutch to therein to selectively appli power to jacket 62.

The jacket 62 has an intake port 5 2 and an outlet port 66 at its ends as well as an exhaust stack 53, which is at the same end thereof as outlet port 65. The header plate ill at one end of jacket 62 has the intake port therethr-ough, which port is in communication with a hopper 52, disposed to feed the material tangentially with regard to drum l6 and into the space between drum Ill and jacket 82 that is designated by the numeral Hi and which constitutes the dehydrating chamber.

A feeder or agitator it is in the throat of hopper '42 to insure an even flow of the comminuted crop or material into dehydrating chamber M. This feeder or agitator i i may be actuated in any suitable manner by appropriate connections to a source of power, not here shown.

Header plate 18 is a stationary element, caps the end of jacket 52, and has the outlet port 66 and the stack 88 disposed thereat.

Jacket 82 is cylindrical, mounted upon frame i2 by rollers 83 and annular, circumscribing tracks 82 respectively, and is rotated about its axis by pinion 3-" and the annular rack or circumscribing chain 85. As will be observed from Fig. 1, power from engine 38 is imparted to 84 and 86 to the end that jacket 6-2 may be rotated in the direction indicated by the arrow in Fig. 5.

In the preferred form of the invention, the structure in the dehydrating chamber for moving the material being treated, longitudinally toward the outlet port 5% from intake port 64, comprises a continuous, spiral strip 88 dividing the dehydrating chamber i l into a number of interconnested compartments substantially isolated from each other so far as the grouping of openings 23 is concerned. Such group and disposition of openings 3.3 as attain the effective aims of the invention, will be hereinafter set down.

Drum if! is somewhat shorter than the length of jacket 62 and a series of lifter blades 9&3 within jacket 62, elevate the material being handled to a point where it slides along these blades 93 and through the outlet port 66 into a chute 92. To the end that packing of the material will not occur on the top of drum i9, jacket 62 is mounted slightly eccentric to drum is for the purpose of providing a space to permit unrestricted passage of high temperature, moist air and such products of combustion as are generated in chamber '14. This space is between the edge of the spiral strip 88 and the outer annular surface of drum is and must always be provided for the positive evacuation of the machine before the aforesaid products of combustion cool to the dew point. Strip 8% is assembled by Welding to the inner face of jacket 62.

After the flame is created within drum E0, the air pressure therein will cause hot air and products of combustion to pass outwardly into the dehydrating chamber l lthrough openings 28. the material being treated progresses toward the outlet port 66, it loses its moisture and therefore, a smaller amount of heat is desired and impingement of hot air upon material in the dehydrating chamber must be diminished as it moves toward the outlet port 86. Accordingly, it has been found highly desirable and efficient to arrange openings 28 substantially as illustrated in Fig. l. These openings communicate with the chambers formed between the several convolutions of strip 88, and since the strip is spiral and does form a number of substantially transverse partitions within chamber 14, the material between these separate convolutions of strip 88 may be classified into that having greater or lesser amounts of moisture content. Agitation of the material is created by the jets of air as it enters the spaces between the convolutions of strip 88. Obviously, when the material first enters dehydrating chamber '56, it has a higher moisture content and as the outlet port '55 is approached, the moisture content will diminish. The number of openings 28, therefore. along the group thereof is greater near the intake port 65 and the distance between the openings 23 is progressively increased as the outlet port ts-is approached.

These openings 28 are outwardly and downwardly inclined, as illustrated in Fig. 5, and are so arranged as to direct jets of hot air and products of combustion into the sub-divided dehydrating chamber i i toward the material being treated, or in a direction opposite to that through which it is being urged by the rotation of jacket 62. In other Words, as the material adheres to the inner surface of jacket 62 and crawls upwardly toward the top of the chamber, it is met by downwardly directed jets of hot air and forced back to the bottom of the jacket 82 where strip 88 will move it longitudinally and closer to the outlet port 86. The drier material will remain near the bottom of chamber 14 as it approaches the port 65 and to avoid burning the material, openings 23 must be spaced progressively closer to the top of drum 10, as the outlet end of the dehydrating chamber 14 is approached. Afewer number of openings 28 will accomplish the same purpose of forcing the material back to the bottom of chamber 14 as the moisture content thereof is diminished.

When the material is first dropped into dehydrating chamber M through hopper l2 and intake port 66, a relatively great amount of moisture is 55 usually therein. Accordingly, it is desirable to initially subject the newly introduced material to a number of hot air blasts to quickly dissipate surface moisture on leafy crops, for example. This surface moisture may be quickly removed by the employment of a number of openings 28 arranged as shown in Fig. 5. These openings 28 are in spaced apart groups below the intake port and directs hot air against the material as it enters the dehydrating chamber and before it is lifted by the moving jacket 82. In fact, as the material enters the left side of the annular dehydrating chamber (Fig. 5) the lefthand group of openings 28 will force the material down to- Ward the bottom of chamber M where another group of openings 28 will direct jets of hot air thereagainst. Thereafter, as the rotating jacket 52 tends to lift the moist crop or material upwardly, the righthand series or group of openings 28 will send jets of air thereagainst. By this 5 time, the material is dry enough to be forced back and kept from riding to the top of drum Hi. If, however, the materials do so ride to the top of the dehydrator chamber M, they will migrate by gravity back to the bottom and into the compartments between the convolutions of strip 88, where they will again be joined by the mass of material and motivated both longitudinally and just beyond the end of drum i and between the end of drum I 6 and outlet port 55, should be the controlling factor, and therefore, a thermocouple -94 is disposed at said point. This thermo-couple 94 is mounted upon the shaft 26 which supports drum l6, and suitable conductors 96 extend therefrom to the automatic control 98 at vave 20. This automatic control which regulates the amount of fuel passing through pipe i6, is obtainable in its entirety upon the open market, and while it forms no part of the invention herein described, it does contribute to the efficient operation of the equipment.

Figs. 6 and 7 illustrate a modified form of the means for motivating the material being treated longitudinally through dehydrating chamber M. In lieu of the spirally arranged strip 88, as above described and illustrated in Figs. 4 and 5, a series of inclined, overlapped plates I053 may be welded or otherwise secured to the inner surface of jacket 62 for the purpose of moving the material. These plates lift and slide the material being dehydrated from the intake port 6 toward the outlet port 66 and their function is analogous to strip 88. Other means for moving the material through dehydrator chamber 14 may be employed if desired, so long as the function of openings 28 is not impaired nor precluded.

The speed of movement through the dehydrating chamber varies with different crops and with the amount of heat applied thereto. It is desirable to maintain a temperature range at thermo-couple 94 at from 375 to 400 F., and when openings 28 have a diameter of one in., from two to six openings 28 are used in the first in. of dehydrating chamber M. From that point on, the number of openings and the height above the bottom of dehydrating chamber 14, may vary to suit conditions. The size and position of the openings is not critical. The manner in which the openings 28 progressively decrease in number as the outlet end is approached, and the manner in which their distance above the bottom of dehydrating chamber 74 is increased, is important however, and constitutes the outstanding element in the entire dehydrating assembly that permits a great throughput of material without burning.

Obviously, dehydrators having physical characteristics different from those illustrated and described might be made without departing from the spirit of the invention or scope of the appended claims.

Having thus described the invention, what is claimed as new and desired to be secured by Let- 'ters Patent is:

.- 1. In a dehydrator of the character described, a stationary drum provided with outwardly directed openings in the wall thereof; means for creatin a fire in the drum; apparatus for directing air under pressure into the drum; a rotatable jacket circumscribing the drum and providing a dehydrating chamber between the drum and the jacket into which are directed the said openings; and means for rotating the drum in a di rection to move the material being treated toward the openings whereby the air passing from the drum through said openings is directed against the material.

2. In a dehydrator of the character described, a stationary drum provided with outwardly directed openings in the wall thereof; means for creating a fire in the drum; apparatus for directing air under pressure into the drum; a rotatable jacket circumscribing the drum and providing a dehydrating chamber between the drum and the jacket into which are directed the said openings; and means for rotating the drum in a direction to move the material being treated upwardly toward the openings whereby to establish counterflow between the air passing from the drum through the said openings and the material in the dehydrating'chamber.

3. In a dehydrator of the character described, a stationary drum provided with outwardly directed openings in the wall thereof; means for creating a fire in the drum; apparatus for directing air under pressure into the drum; a rotatable jacket circumscribing the drum and providing a dehydrating chamber between the drum and the jacket into which are directed the said openings; and means for rotating the drum in a direction to move the material being treated toward the openings whereby the air passing from the drum through said openings is directed against the material, said openings being arranged in a path extending substantially longitudinally ofthe drum, the distance between said openings being progressively greater as the outlet end of the dehydratin chamber is approached.

i. In a dehydrator of the character described, stationary drum provided with outwardly directed openings in the wall thereof; means for creating a fire in the drum; apparatus for directing air under pressure into the drum; a rotatable jacket circumscribing the drum and providing a dehydrating chamber between the drum and the jacket into which are directed the said openings; means for rotating the drum; and members in the dehydrating chamber for directing the material therein longitudinally therealong, said. members being formed to divide the dehydrating chamber into a series of transverse compartments each having a plurality of said openings in communication therewith.

5. In a dehydrator of the character described, a stationary drum provided with outwardly directed openings in the wall thereof; means for creating a fire in the drum; apparatus for directing air under pressure into the drum; a rotatable jacket circumscribing the drum and providing a dehydrating chamber between the drum and the jacket into which are directed the said openings; means for rotating the drum; and members in the dehydrating chamber for directing the material therein longitudinally therealong, said members being formed to divide the dehydrating chamber into a series of transverse compartments each having a plurality of said openings in communication therewith, said openings for the successive compartments being progressively fewer in number as the outlet end of the chamber is approached.

6. In a dehydrator of the character described, a stationary drum provided with outwardlydirected openings in the wall thereof; means for creating a fire in the drum; apparatus for directing air under pressure into the drum; a rotatable jacket circumscribing the drum and providing a dehydrating chamber between the drum and the jacket into which are directed the said openings; means for rotating the drum; and members in the dehydrating chamber for directing the material therein longitudinally therealong, said members being formed to divide the dehydrating chamber into a series of transverse compartments each having a plurality of said openings in communication therewith, said openings for the successive compartments being progressively fewer in number and disposed progressively higher from the bottom of the compartment as the of the chamber is approached.

'7. In a dehydrator of the character described, astationary drum provided with outwardly directed openings in the wall thereof; means for creating a fire in the drum; perforated pipes extending into the drum to direct air under pressure into the drum; apparatus for feeding such air into the pipes; a rotatable jacket having an intake and an outlet port therein and providing a dehydrating chamber between the drum and the jacket into which are directed the said openings; means for rotating the drum; and a spirally arranged, internal rib on the inner face of the jacket for dividing the chamber into a number of compartments and for moving the material being treated from the intake toward the outlet port.

8. In a dehydrator of the character described, a stationary drum provided with outwardly directed openings in the wall thereof; means for creating a fire in the drum; perforated pipes extending into the drum to direct air under pressure into the drum; apparatus for feeding such air into the pipes; a rotatable jacket having an intake and an outlet port therein and providing a dehydrating chamber between the drum and the jacket into which are directed the said openings; means for rotating the drum; and a spirally arranged, internal rib on the inner face of the jacket for dividing the chamber into a number of compartments and for moving the material being treated from the intake toward the outlet port, said openings being arranged in a path extending upwardly from a point adjacent to the intake port to a point near the outlet port of the jacket.

9. In a dehydrator of the character described, a stationary drum provided with outwardly directed openings in the wall thereof; means for creating a fire in the drum; perforated pipes extending into the drum to direct air under pressure into the drum; apparatus for feeding such air into the pipes; a rotatable jacket having an intake and an outlet port therein and providing a dehydrating chamber between the drum and the jacket into which are directed the said openings; means for rotating the drum; and a spirally arranged, internal rib on the inner face of the jacket for dividing the chamber into a number of compartments and for moving the material being treated from the intake toward the outlet port, said openings being arranged in a path extending up wardly from a point adjacent to the intake port to a point near the outlet port of the jacket, said openings being spaced progressively farther apart outlet end Gil as the outlet port is approached whereby less hot air is introduced to the material being treated as it progresses through the dehydrating chamber.

10. In a dehydrator of the character described, a stationary drum provided with outwardly directed openings in the wall thereof; means for creating a fire in the drum; perforated pipes extending intothe drum to direct air under pressure into the drum; apparatus for feeding such air into the pipes; a rotatable jacket having an intake and an outlet port therein and providing a dehydrating chamber between the drum and the jacket into which are directed the said openings; means for rotating the drum; and a spirally arranged, internal rib on the inner face of the jacket for dividing the chamber into a number of compartments and for moving the material being treated from the intake toward the outlet port, said openings being arranged in a path extending upwardly from a point adjacent to the intake port to a point near the outlet port of the jacket, said openings being spaced progressively farther apart as the outlet port is approached whereby less hot air is introduced to the material being treated as it progresses through the dehydrating chamber, said openings being directed downwardly toward the bottom of the dehydrating chamber to establish counterfiow between the material being treated and the air passing from within the drum to the dehydrating chamber.

ll. In a dehydrator of the character described, a stationary drum provided with openings in the side Wall thereof; means for creating a fire in the drum; apparatus for directing air under pressure into the drum to be heated and forced out through the openings; a jacket, having an intake port at one end and an outlet port at the other end thereof, circumscribing the drum in spaced relation thereto to form a dehydrating chamber between the drum and the jacket; and structure in the dehydrating chamber for moving the material longitudinally along the dehydrating chamber toward the outlet port thereof and upwardly from the lowermost portion of the said chamber, said openings being arranged to direct jets of hot air against the material to limit its upward movement.

12. In a dehydrator of the character described,

a stationary drum provided with openings in the side wall thereof; means for creating a fire in the drum; apparatus for directing air under pressure into the drum to be heated and forced out through the openings; a jacket, having an intake port at one end and an outlet port at the other end thereof, circumscribing the drum in spaced relation thereto to form a dehydrating chamber between the drum and the jacket; and structure in the dehydrating chamber for moving the material longitudinally along the dehydrating chamber toward the outlet port thereof and upwardly from the lowermost portion of the said chamber, said openings being arranged to direct jets of hot air against the material to limit its upward movement, said openings being progressively higher as the outlet port is approached.

13. In a dehydrator of the character described, a stationary drum provided with openings in the side wall thereof; means for creating a fire in the drum; apparatus for directing air under pressure into the drum to be heated and forced out through the openings; a jacket, having an intake port at one end and an outlet port at the other end thereof, circumscribing the drum in spaced relation thereto to form a dehydrating chamber between the drum and the jacket; and structure in the dehydrating chamber for moving the material longitudinally along the dehydrating chamber toward the outlet port thereof and upwardly from the lowermost portion of the said chamber, said openings being arranged to direct jets of hot air against the material to limit its upward movement, said openings being progressively higher as the outlet port is approached, said openings being spaced progressively farther apart as the outlet port is approached.

14. In a dehydrator of the character described, a stationary drum provided with openings in the side wall thereof; means for creating a fire in the drum; apparatus for directing air under pressure into the drum to be heated and forced out through the openings; a jacket, having an intake port at one end and an outlet port at the other end thereof, circumscribing the drum in spaced relation thereto to form a dehydrating chamber between the drum and the jacket; and structure in the dehydrating chamber for moving the material longitudinally along the dehydrating chamber toward the outlet port thereof and upwardly from the lowermost portion of the said chamber, said openings being arranged to direct jets of hot air against the material to limit its upward moveings; means for rotating the drum;

ment, certain of said openings being arranged in spaced apart groups near the intake port and disposed to direct hot air against the material as it enters the dehydrating chamber and before it is elevated by the said structure for moving the material.

15. In a dehydrator of the character described, a stationary drum provided with outwardly directed openings in the wall thereof; means for creating a fire in the drum; perforated pipes extending into the drum to direct air under pressure into the drum; apparatus for feeding such air into the pipes; a rotatable jacket having an intake and an outlet port therein and providing a dehydrating chamber between the drum and the jacket into which are directed the said openand a spirally arranged, internal rib on the inner face of the jacket for dividing the chamber into a number of compartments and for moving the material being treated from the intake toward the outlet port, said openings being in communication with the said compartments and arranged in progressively decreasing numbers as the outlet port is approached to provide a progressively reduced temperature in the successive compartments.

ADELBERT P. NICHOLS, JR. 

